The Red List Index (RLI; Butchart et al. 2004, 2005, 2007) can be disaggregated to show trends for species in different ecosystems. It shows that species in terrestrial, freshwater and marine ecosystems (including coastal habitats) have deteriorated in status over the last 20 years. Marine species are of particular concern: they are substantially more threatened on average (with the lowest RLI values), and have declined faster.

The Red List Index for the birds in different ecosystems for 1988–2008.

Analysis of data held in BirdLife’s World Bird Database (2008).

The Red List Index (RLI) of bird species survival in different ecosystems (n = 1,307 non-Data Deficient freshwater species, 9,686 terrestrial species and 336 marine and coastal species) shows the proportion of species expected to remain extant in the near future without additional conservation action. An RLI value of 1.0 equates to all species being categorised as Least Concern, and hence that none are expected to go extinct in the near future. An RLI value of zero indicates that all species have gone Extinct. Species are included in the calculations for all ecosystems in which they occur regularly, but status changes driving RLI trends are assigned only to the ecosystem(s) in which the processes driving them occurred.